CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of and priority from
U.S. Provisional Patent Application No. 62/778,802 entitled "PCIe High Power Card Edge Connector" and filed December 12, 2018, the entire
disclosure of which is incorporated herein by reference.
FIELD
[0002] This disclosure pertains to computing systems, and in particular (but not exclusively)
to card edge connectors for power delivery to add-in card devices, such as PCIe-compatible
add-in cards.
BACKGROUND
[0003] Advances in semi-conductor processing and logic design have permitted an increase
in the amount of logic that may be present on integrated circuit devices. As a corollary,
computer system configurations have evolved from a single or multiple integrated circuits
in a system to multiple cores, multiple hardware threads, and multiple logical processors
present on individual integrated circuits, as well as other interfaces integrated
within such processors. A processor or integrated circuit typically comprises a single
physical processor die, where the processor die may include any number of cores, hardware
threads, logical processors, interfaces, memory, controller hubs, etc.
[0004] Not only have developments in computing enabled more processing power to be implemented
in smaller packages, demand in the high-performance computing market (i.e. server
space) has also increased. For instance, in modern servers, there is typically not
only a single processor with multiple cores, but also multiple physical processors
(also referred to as multiple sockets) to increase the computing power. But as the
processing power grows along with the number of devices in a computing system, the
communication between sockets and other devices becomes more critical. In fact, interconnects
have grown from more traditional multi-drop buses that primarily handled electrical
communications to full blown interconnect architectures that facilitate fast communication.
Further, as the demand for future high-performance processors increases, demand grows
for interconnect architectures capable of supporting the corresponding high data rates
made available by next generation processors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005]
FIG. 1 illustrates an embodiment of a computing system including an interconnect architecture.
FIG. 2 illustrates an embodiment of a interconnect architecture including a layered
stack.
FIG. 3 illustrates an embodiment of a request or packet to be generated or received
within an interconnect architecture.
FIG. 4 illustrates an embodiment of a transmitter and receiver pair for an interconnect
architecture.
FIG. 5 illustrates an embodiment of a PCIe-compatible add-in card with additional
edge finger tabs for providing power delivery to the add-in card.
FIG. 6 illustrates an embodiment of coupling between an example add-in card and an
example edge card connector.
FIG. 7 illustrates another embodiment of coupling between an example add-in card and
an example edge card connector.
FIG. 8 illustrates an embodiment of an example add-in card edge finger tab with a
chamfered outer edge.
FIGS. 9A-9D illustrate embodiments of edge card connectors for communicably coupling
add-in cards to a baseboard and for providing additional power delivery to the add-in
card through additional connection mechanisms.
FIG. 10 illustrates an embodiment of a system that may incorporate PCIe-compatible
add-in cards with additional edge connectors for providing power delivery.
FIG. 11 illustrates an embodiment of a block diagram for a computing system including
a multicore processor.
FIG. 12 illustrates an embodiment of a block for a computing system including multiple
processors.
DETAILED DESCRIPTION
[0006] In the following description, numerous specific details are set forth, such as examples
of specific types of processors and system configurations, specific hardware structures,
specific architectural and micro architectural details, specific register configurations,
specific instruction types, specific system components, specific measurements/heights,
specific processor pipeline stages and operation etc. in order to provide a thorough
understanding of the present disclosure. It will be apparent, however, to one skilled
in the art that these specific details need not be employed to practice the present
disclosure. In other instances, well known components or methods, such as specific
and alternative processor architectures, specific logic circuits/code for described
algorithms, specific firmware code, specific interconnect operation, specific logic
configurations, specific manufacturing techniques and materials, specific compiler
implementations, specific expression of algorithms in code, specific power down and
gating techniques/logic and other specific operational details of computer system
haven't been described in detail in order to avoid unnecessarily obscuring the present
disclosure.
[0007] Although the following embodiments may be described with reference to enhancements
in specific computing systems, such as in computing platforms or microprocessors,
other embodiments are applicable to other types of integrated circuits and logic devices.
Similar techniques and teachings of embodiments described herein may be applied to
other types of circuits or semiconductor devices that may also benefit from better
energy efficiency and energy conservation. For example, the disclosed embodiments
are not limited to desktop computer systems or Ultrabooks™. And may be also used in
other devices, such as handheld devices, tablets, other thin notebooks, systems on
a chip (SOC) devices, and embedded applications. Some examples of handheld devices
include cellular phones, Internet protocol devices, digital cameras, personal digital
assistants (PDAs), and handheld PCs. Embedded applications typically include a microcontroller,
a digital signal processor (DSP), a system on a chip, network computers (NetPC), set-top
boxes, network hubs, wide area network (WAN) switches, or any other system that can
perform the functions and operations taught below. Moreover, the apparatus', methods,
and systems described herein are not limited to physical computing devices, but may
also relate to software optimizations for energy conservation and efficiency. As will
become readily apparent in the description below, the embodiments of methods, apparatus',
and systems described herein (whether in reference to hardware, firmware, software,
or a combination thereof) are vital to a 'green technology' future balanced with performance
considerations.
[0008] As computing systems are advancing, the components therein are becoming more complex.
As a result, the interconnect architecture to couple and communicate between the components
is also increasing in complexity to ensure bandwidth requirements are met for optimal
component operation. Furthermore, different market segments demand different aspects
of interconnect architectures to suit the market's needs. For example, servers require
higher performance, while the mobile ecosystem is sometimes able to sacrifice overall
performance for power savings. Yet, it's a singular purpose of most fabrics to provide
highest possible performance with maximum power saving. Below, a number of interconnects
are discussed, which would potentially benefit from aspects of the embodiments described
herein.
[0009] One interconnect fabric architecture includes the Peripheral Component Interconnect
(PCI) Express (PCIe) architecture. A primary goal of PCIe is to enable components
and devices from different vendors to inter-operate in an open architecture, spanning
multiple market segments; Clients (Desktops and Mobile), Servers (Standard, Rack Scale,
and Enterprise), and Embedded and Communication devices. PCI Express is a high performance,
general purpose I/O interconnect defined for a wide variety of future computing and
communication platforms. Some PCI attributes, such as its usage model, load-store
architecture, and software interfaces, have been maintained through its revisions,
whereas previous parallel bus implementations have been replaced by a highly scalable,
fully serial interface. The more recent versions of PCI Express take advantage of
advances in point-to-point interconnects, Switch-based technology, and packetized
protocol to deliver new levels of performance and features. Power Management, Quality
Of Service (QoS), Hot-Plug/Hot- Swap support, Data Integrity, and Error Handling are
among some of the advanced features supported by PCI Express.
[0010] Referring to FIG. 1, an embodiment of a fabric composed of point-to-point Links that
interconnect a set of components is illustrated. System 100 includes a processor 105
and system memory 110 coupled to controller hub 115. The processor 105 includes any
processing element, such as a microprocessor, a host processor, an embedded processor,
a co-processor, or other processor. The processor 105 may be coupled to controller
hub 115 through front-side bus (FSB) 106. In one embodiment, FSB 106 may be a serial
point-to-point interconnect as described below. In another embodiment, link 106 includes
a serial, differential interconnect architecture that is compliant with different
interconnect standard. In some implementations, the system may include logic to implement
multiple protocol stacks and further logic to negotiation alternate protocols to be
run on top of a common physical layer, among other example features.
[0011] System memory 110 includes any memory device, such as random access memory (RAM),
non-volatile (NV) memory, or other memory accessible by devices in system 100. System
memory 110 is coupled to controller hub 115 through memory interface 116. Examples
of a memory interface include a double-data rate (DDR) memory interface, a dual-channel
DDR memory interface, and a dynamic RAM (DRAM) memory interface.
[0012] Examples of controller hub 115 include a chipset, a platform controller hub (PCH),
a memory controller hub (MCH), a northbridge, an interconnect controller hub (ICH)
a southbridge, and a root controller/hub. The term chipset may refer, in some cases,
to a platform controller hub (PCH), an in other cases, may refer to two physically
separate controller hubs, i.e. a memory controller hub (MCH) coupled to an interconnect
controller hub (ICH). In some embodiments, controller hub 115 is a root hub, root
complex, or root controller in a Peripheral Component Interconnect Express (PCIe or
PCIE) interconnection hierarchy. Peer-to-peer routing may optionally be supported
through the controller hub 115 as a root complex. In other embodiments, the processor
105 may include root hub, root complex, and/or root controller functionality in a
PCIe interconnection hierarchy, while the controller hub 115 is to communicate with
I/O devices, in a similar manner as described below.
[0013] In the example shown, controller hub 115 is coupled to switch/bridge 120 through
serial link 119. Input/output modules 117 and 121, which may also be referred to as
interfaces/ports 117 and 121, include/implement a layered protocol stack to provide
communication between controller hub 115 and switch 120. In one embodiment, multiple
devices are capable of being coupled to switch 120. In the example shown, switch 120
is coupled to device 125 through serial link 123, and input/output modules 122 and
126, which may also be referred to as interfaces/ports 122 and 126, include/implement
a layered protocol stack to provide communication between switch 120 and device 125.
The switch/bridge 120 routes packets/messages from device 125 upstream, i.e. up a
hierarchy towards a root complex, to controller hub 115 and downstream, i.e. down
a hierarchy away from a root controller, from processor 105 or system memory 110 to
device 125. Switch 120, in one embodiment, is referred to as a logical assembly of
multiple virtual PCI-to-PCI bridge devices.
[0014] Device 125 includes any internal or external device or component to be coupled to
an electronic system, such as an I/O device, a Network Interface Controller (NIC),
an add-in card, an audio processor, a network processor, a hard-drive, a storage device,
a CD/DVD ROM, a monitor, a printer, a mouse, a keyboard, a router, a portable storage
device, a Firewire device, a Universal Serial Bus (USB) device, a scanner, and other
input/output devices. Often in the PCIe vernacular, such as device, is referred to
as an endpoint. Although not specifically shown, device 125 may include a PCIe to
PCI/PCI-X bridge to support legacy or other version PCI devices. Endpoint devices
in PCIe are often classified as legacy, PCIe, or root complex integrated endpoints.
[0015] Graphics accelerator 130 is also coupled to controller hub 115 through serial link
132. In one embodiment, graphics accelerator 130 is coupled to an MCH, which is coupled
to an ICH. Switch 120, and accordingly I/O device 125, is then coupled to the ICH.
I/O modules 131 and 118 are also to implement a layered protocol stack to communicate
between graphics accelerator 130 and controller hub 115. Similar to the MCH discussion
above, a graphics controller or the graphics accelerator 130 itself may be integrated
in, or coupled to, processor 105. Further, one or more links of the system can include
one or more extension devices, such as retimers, repeaters, etc.
[0016] Turning to FIG. 2 an embodiment of a layered protocol stack is illustrated. Layered
protocol stack 200 includes any form of a layered communication stack, such as a Quick
Path Interconnect (QPI) stack, an Ultra Path Interconnect (UPI) stack, a PCIe stack,
a next generation high performance computing interconnect stack, or other layered
stack. Although the discussion immediately below in reference to FIGS. 1-4 are in
relation to a PCIe stack, the same concepts may be applied to other interconnect stacks.
In one embodiment, protocol stack 200 is a PCIe protocol stack including transaction
layer 205, link layer 210, and physical layer 220. An interface, such as interfaces
117, 118, 121, 122, 123, 127, 128, and 131 in FIG. 1, may be represented as communication
protocol stack 200. Representation as a communication protocol stack may also be referred
to as a module or interface implementing/including a protocol stack.
[0017] PCI Express uses packets to communicate information between components. Packets are
formed in the Transaction Layer 205 and Data Link Layer 210 to carry the information
from the transmitting component to the receiving component. As the transmitted packets
flow through the other layers, they are extended with additional information necessary
to handle packets at those layers. At the receiving side the reverse process occurs
and packets get transformed from their Physical Layer 220 representation to the Data
Link Layer 210 representation and finally (for Transaction Layer Packets) to the form
that can be processed by the Transaction Layer 205 of the receiving device.
Transaction Layer
[0018] In one embodiment, transaction layer 205 is to provide an interface between a device's
processing core and the interconnect architecture, such as data link layer 210 and
physical layer 220. In this regard, a primary responsibility of the transaction layer
205 is the assembly and disassembly of packets (i.e., transaction layer packets, or
TLPs). The translation layer 205 typically manages credit-base flow control for TLPs.
PCIe implements split transactions, i.e. transactions with request and response separated
by time, allowing a link to carry other traffic while the target device gathers data
for the response.
[0019] In addition PCIe utilizes credit-based flow control. In this scheme, a device advertises
an initial amount of credit for each of the receive buffers in Transaction Layer 205.
An external device at the opposite end of the link, such as controller hub 115 in
FIG. 1, counts the number of credits consumed by each TLP. A transaction may be transmitted
if the transaction does not exceed a credit limit. Upon receiving a response an amount
of credit is restored. An advantage of a credit scheme is that the latency of credit
return does not affect performance, provided that the credit limit is not encountered.
[0020] In one embodiment, four transaction address spaces include a configuration address
space, a memory address space, an input/output address space, and a message address
space. Memory space transactions include one or more of read requests and write requests
to transfer data to/from a memory-mapped location. In one embodiment, memory space
transactions are capable of using two different address formats, e.g., a short address
format, such as a 32-bit address, or a long address format, such as 64-bit address.
Configuration space transactions are used to access configuration space of the PCIe
devices. Transactions to the configuration space include read requests and write requests.
Message space transactions (or, simply messages) are defined to support in-band communication
between PCIe agents.
[0021] Therefore, in one embodiment, transaction layer 205 assembles packet header/payload
206. Format for current packet headers/payloads may be found in the PCIe specification
published by the PCI-SIG at the PCIe specification website.
[0022] Quickly referring to FIG. 3, an embodiment of a PCIe transaction descriptor is illustrated.
In one embodiment, transaction descriptor 300 is a mechanism for carrying transaction
information. In this regard, transaction descriptor 300 supports identification of
transactions in a system. Other potential uses include tracking modifications of default
transaction ordering and association of transaction with channels.
[0023] Transaction descriptor 300 includes global identifier field 302, attributes field
304 and channel identifier field 306. In the illustrated example, global identifier
field 302 is depicted comprising local transaction identifier field 308 and source
identifier field 310. In one embodiment, global transaction identifier 302 is unique
for all outstanding requests.
[0024] According to one implementation, local transaction identifier field 308 is a field
generated by a requesting agent, and it is unique for all outstanding requests that
require a completion for that requesting agent. Furthermore, in this example, source
identifier 310 uniquely identifies the requestor agent within a PCIe hierarchy. Accordingly,
together with source ID 310, local transaction identifier 308 field provides global
identification of a transaction within a hierarchy domain.
[0025] Attributes field 304 specifies characteristics and relationships of the transaction.
In this regard, attributes field 304 is potentially used to provide additional information
that allows modification of the default handling of transactions. In one embodiment,
attributes field 304 includes priority field 312, reserved field 314, ordering field
316, and no-snoop field 318. Here, priority sub-field 312 may be modified by an initiator
to assign a priority to the transaction. Reserved attribute field 314 is left reserved
for future, or vendor-defined usage. Possible usage models using priority or security
attributes may be implemented using the reserved attribute field.
[0026] In this example, ordering attribute field 316 is used to supply optional information
conveying the type of ordering that may modify default ordering rules. According to
one example implementation, an ordering attribute of "0" denotes default ordering
rules are to apply, wherein an ordering attribute of "1" denotes relaxed ordering,
wherein writes can pass writes in the same direction, and read completions can pass
writes in the same direction. Snoop attribute field 318 is utilized to determine if
transactions are snooped. As shown, channel ID Field 306 identifies a channel that
a transaction is associated with.
Link Layer
[0027] Link layer 210, also referred to as data link layer 210, acts as an intermediate
stage between transaction layer 205 and the physical layer 220. In one embodiment,
a responsibility of the data link layer 210 is providing a reliable mechanism for
exchanging Transaction Layer Packets (TLPs) between two components a link. One side
of the Data Link Layer 210 accepts TLPs assembled by the Transaction Layer 205, applies
packet sequence identifier 211, i.e. an identification number or packet number, calculates
and applies an error detection code, i.e. CRC 212, and submits the modified TLPs to
the Physical Layer 220 for transmission across a physical to an external device.
Physical Layer
[0028] In one embodiment, physical layer 220 includes logical sub block 221 and electrical
sub-block 222 to physically transmit a packet to an external device. Here, logical
sub-block 221 is responsible for the "digital" functions of Physical Layer 220. In
this regard, the logical sub-block includes a transmit section to prepare outgoing
information for transmission by physical sub-block 222, and a receiver section to
identify and prepare received information before passing it to the Link Layer 210.
[0029] Physical block 222 includes a transmitter and a receiver. The transmitter is supplied
by logical sub-block 221 with symbols, which the transmitter serializes and transmits
onto to an external device. The receiver is supplied with serialized symbols from
an external device and transforms the received signals into a bit-stream. The bit-stream
is de-serialized and supplied to logical sub-block 221. In one embodiment, an 8b/10b
transmission code is employed, where ten-bit symbols are transmitted/received. Here,
special symbols are used to frame a packet with frames 223. In addition, in one example,
the receiver also provides a symbol clock recovered from the incoming serial stream.
[0030] As stated above, although transaction layer 205, link layer 210, and physical layer
220 are discussed in reference to a specific embodiment of a PCIe protocol stack,
a layered protocol stack is not so limited. In fact, any layered protocol may be included/implemented.
As an example, an port/interface that is represented as a layered protocol includes:
(1) a first layer to assemble packets, i.e. a transaction layer; a second layer to
sequence packets, i.e. a link layer; and a third layer to transmit the packets, i.e.
a physical layer. As a specific example, a common standard interface (CSI) layered
protocol is utilized.
[0031] Referring next to FIG. 4, an embodiment of a PCIe serial point to point fabric is
illustrated. Although an embodiment of a PCIe serial point-to-point link is illustrated,
a serial point-to-point link is not so limited, as it includes any transmission path
for transmitting serial data. In the embodiment shown, a basic PCIe link includes
two, low-voltage, differentially driven signal pairs: a transmit pair 406/411 and
a receive pair 412/407. Accordingly, device 405 includes transmission logic 406 to
transmit data to device 410 and receiving logic 407 to receive data from device 410.
In other words, two transmitting paths, i.e. paths 416 and 417, and two receiving
paths, i.e. paths 418 and 419, are included in a PCIe link.
[0032] A transmission path refers to any path for transmitting data, such as a transmission
line, a copper line, an optical line, a wireless communication channel, an infrared
communication link, or other communication path. A connection between two devices,
such as device 405 and device 410, is referred to as a link, such as link 415. A link
may support one or more lanes - each lane representing a set of differential signal
pairs (one pair for transmission, one pair for reception). To scale bandwidth, a link
may aggregate multiple lanes denoted by xN, where N is any supported link width, such
as 1, 2, 4, 8, 12, 16, 32, 64, or wider.
[0033] A differential pair refers to two transmission paths, such as lines 416 and 417,
to transmit differential signals. As an example, when line 416 toggles from a low
voltage level to a high voltage level, i.e. a rising edge, line 417 drives from a
high logic level to a low logic level, i.e. a falling edge. Differential signals potentially
demonstrate better electrical characteristics, such as better signal integrity, i.e.
cross-coupling, voltage overshoot/undershoot, ringing, etc. This allows for better
timing window, which enables faster transmission frequencies.
[0034] In some implementations, a high-performance interconnect and corresponding interconnect
protocol (e.g., such as a next generation PCIe-based interconnect) may be provided
that is capable of operating at high speeds such as 25 GT/s and/or 32 GT/s. In one
example, two speeds may be defined for the high performance interconnect, one at 25
GT/s and 32 GT/s, based on the characteristics determined for the channel (e.g., during
link training). The interconnect, in one implementation, may be backwards compatible
with existing PCIe generations and speeds provided for these generations (e.g., 8
GT/s, 16 GT/s, etc.).
[0035] FIG. 5 illustrates an embodiment of a PCIe-compatible add-in card 500 with additional
edge finger tabs 506, 508 for providing power delivery to the add-in card. PCIe-compatible
may refer to compatibility with one or more Peripheral Component Interconnect Express
specifications published by the PCI-SIG, such as, for example, versions or revisions
the PCI Express Base Specification, the PCI Express Card Electromechanical (CEM) Specification,
or other specifications published by the PCI-SIG. The example add-in card 500 may
be configured to mate with a baseboard (e.g., a motherboard or other type of printed
circuit board (PCB)) via an edge connector. The baseboard may include one or more
processors and an interconnect architecture for communicably coupling the add-in card
500 and the one or more processors. Once mated with a baseboard, the add-in card 500
may provide certain functionality as described above with respect to FIGS. 1-4. For
example, the add-in card 500 may be implemented similar to I/O device 125 of FIG.
1 in an interconnect architecture and may communicate with a processor according to
the examples described in FIGS 2-4. The add-in card 500 may include fewer or additional
components or features than those shown in FIG. 5.
[0036] In the example shown in FIG. 5, the add-in card 500 includes a circuit board region
502 that includes a number of circuit components (e.g., 514) for implementing the
functionality of the add-in card 500. For example, the add-in card 500 may include
graphics processing circuitry and the circuit board region 502 may accordingly include
one or more GPUs, memory, and other circuit components for implementing such functionality.
The add-in card 500 also includes an edge finger tab region 504 that extends from
the circuit board region 502 at the bottom end 525 of the card 500 (opposite the top
end 515 of the card 500). In the example shown, the edge finger tab region 504 includes
two edge finger tabs 504A, 504B. The edge finger tab 504A may be a fixed size for
different add-in cards (e.g., based on PCIe specifications), while the edge finger
tab 504B may vary in size for different add-in cards (e.g., may be compatible with
x1, x4, x8, or x16 PCIe connectors). In the example shown ,the edge finger tab region
504 corresponds to an x16 PCIe-compatible edge finger region. In some cases, the two
edge fingers tabs 504A, 504B may be considered or referred to as a single edge finger
tab (e.g., a PCIe-compatible edge finger tab). The edge finger tab region 504 may
be configured to mate with an edge connection mechanism of a baseboard and may include
one or more electrical contacts or traces (which may be referred to as "edge fingers")
to provide signaling between the circuit components of the circuit board region 502
and components of the baseboard (e.g., a processor). In some cases, the edge finger
tab region 504 may also include one or more electrical contacts or traces to provide
power delivery from a power supply (e.g., connected to or integrated with the baseboard)
to the circuit components. In some implementations, the edge finger tab region 504
may be configured to provide up to 75 W of power to the circuit components in the
circuit board region 502.
[0037] In some instances, PCIe card and system vendors may desire implementations that involve
supplying higher power to a PCIe card at a level beyond the defined capacity of traditional
PCIe edge connectors. For instance, while the PCIe Card Electromechanical (CEM) Specification,
permits supplemental power delivery to an add-in card by means of a cable (e.g., connected
between cable connector 511 and a power supply) to provide a combined slot and cable
total of 300 Watts, some applications may actually demand 500-600 Watts, or higher.
Further, there is a demand for power delivered on a nominal 48 volt DC rail, which
is currently not supported in the 4.0 CEM specification, among other example shortcomings.
Traditionally, solutions to exceed 300 Watts may involve proprietary cables from various
suppliers. Moreover, any previous or current solutions to supplying power beyond 300
Watts are not compliant with PCIe specifications, so there is no guarantee they will
work in a given system. These approaches might require chassis-level agreement between
the add-in card vendor and system baseboard vendor to provide the extra power and
cooling, among other complexities. In contrast, interoperability between add-in cards
that are PCIe specification compliant and system baseboards is generally guaranteed.
Further, power delivery by means of cables, such as by supplemental cables connected
to cable connector 511 (e.g., an extension to the current 12V auxiliary cable approach),
may further obstruct airflow and add cost.
[0038] As an alternative to a cabled solution, an add-in card may be implemented with a
simple card edge extension to add contacts beyond the current, defined edge finger
pinfield. However, as the add-in card outline may be strictly defined by the PCIe
spec, the addition of the incremental edge finger tabs beyond the established card
perimeter may violate backward compatibility. Further, the downward protrusion of
the edge additional finger tab would cause mechanical interference with baseboard
components on some legacy system baseboards. Accordingly, an add-in card adapted,
for instance, to compute-heavy applications requiring a supply of power at a level
that beyond the capacity of the current PCIe card connection mechanisms (e.g., the
75W that may be provided by the electrical contacts in the edge finger tab region
504), may be implemented while addressing issues related to backward compatibility
and mechanical interference. For example, in some embodiments, an add-in card may
be provided, which is capable of operating at 500-600 Watts or higher, while delivering
power on a nominal 48 volt DC (VDC) rail instead of or in addition to the existing
+12 VDC and +3.3 VDC power rails on which power is delivered through the edge finger
tab region 504, or on a supplemental 12 VDC rail in addition to the existing +12 VDC
and +3.3 VDC power rails.
[0039] Accordingly, an example add-in card 500 is illustrated showing the inclusion of additional
PCB edge finger tabs 506, 508 that extend from the circuit board region 502 (in-line
with the edge finger tab region 504) and are configured (similar to the edge finger
tab region 504) to mate with respective edge connection mechanisms of a baseboard.
The edge finger tabs 506, 508 may include one or more electrical contacts or traces
(which may be referred to as "edge fingers") that provide additional power delivery
to the circuit components of the circuit board region 502 beyond the power delivery
provided by the edge finger tab region 504. For example, in some embodiments, the
electrical contacts on the edge finger tabs 506, 508 may deliver additional power
to the add-in card 500 on one or more of a 3.3 VDC rail, a 12 VDC rail, or a 48 VDC
rail.
[0040] The power delivery provided via the edge finger tabs 506, 508 may be in addition
to power delivery via the edge finger region 504 (which may provide, for example,
a 3.3 VDC rail and a 12 VDC rail) or power delivery via the cable connector 511 (which
may provide, for example, a 48 VDC rail). For instance, in the example shown, the
edge finger tabs 506, 508 and the cable connector each provide a 48 VDC rail voltage,
which is fed to a voltage regulator 513. The voltage regulator 513 down converts the
48 VDC rail voltages to one or more rail voltages (e.g., 1.1 VDC as shown) that may
be suitable for use by the circuit components 514. It will be understood that the
voltage regulator 513 may also receive other rail voltages for conversion, such as
the 3.3 VDC or 12 VDC rail voltages provided by the edge finger region 504.
[0041] In some cases, the edge finger tabs 506, 508 may be connected to a different power
supply than the cable connector 511, or each finger tab 506, 508 may be connected
to a different power supply. This may cause power to be fed from one power connector
through the baseboard to another power connector, which may be undesired. For instance,
referring to the example shown in FIG. 5, if power supplies were connected to both
cable connector 511 and one or both of edge finger tabs 506, 508, power supplied through
cable connector 511 may flow through the board and "back feed" a baseboard power supply.
This may cause contention in the voltage regulator 513 or may cause currents in one
or more of the connectors to exceed their rated current output, as the connector would
see not only the power demand of the add-in card 500 itself, but also the demand of
any other devices on the same bus, such as neighboring add-in cards.
[0042] Therefore, in some embodiments, current blocking elements (e.g., 507, 509, 512) may
be implemented in each of the input paths for the add-in card's power connectors (e.g.,
506, 508, 511). The current blocking elements may selectively accept power from only
one of the add-in card's power connectors. This would permit the unused power supply
connectors to "float", with no power drawn and no direct connection to the other power
input connectors. The current blocking elements may be implemented, in some embodiments,
as field effect transistors (FETs). In some embodiments (e.g., as shown in FIG. 5),
the current blocking elements may be implemented as dedicated power switches connected
to the respective power inputs to the add-in card. In other embodiments, the current
blocking elements may be integrated into the voltage regulator 513 or other voltage
regulators of the circuit board portion.
[0043] In the example shown, the edge finger tab 506 is between the edge finger tab region
504 and the end 510 of the card 500 that is configured to face an outer edge of the
baseboard (e.g., near a rear panel of a system chassis) when the add-in card is mated
with the baseboard, and the edge finger tab 508 is between the edge finger tab region
504 and the end 520 of the card 500 (opposite the end 510) that is configured to face
inward (e.g., toward a more central area of a system chassis) relative to the baseboard
when the add-in card is mated with the baseboard. In some embodiments, the add-in
card 500 may include only one of edge finger tabs 506, 508 rather than both as shown.
[0044] In some implementations (e.g., as shown), the edge finger tabs 506, 508 may be formed
such that they are compatible with aspects of current PCIe specifications. For instance,
in the example shown, some additional power delivery connectors are implemented in
the edge finger tab 506, which is a PCIe-compatible feature for preventing the add-in
card 500 from being inserted into a legacy PCI edge card connection mechanism (sometimes
referred to as a "blocking tab" or with similar nomenclature). Likewise, some additional
power delivery connectors are implemented in the edge finger tab 508, which is a PCIe-compatible
feature for mating with a retention mechanism of a baseboard (sometimes referred to
as a "hockey stick feature" or with similar nomenclature). Accordingly, the example
edge finger tab 506 is generally rectangular shaped, and the example edge finger tab
508 is generally hockey stick shaped. In some instances, the outer edges (i.e., those
that face toward the baseboard connector) of each of the edge finger tabs 504, 506,
508 may be chamfered similar to the chamfered outer edge 810 shown in FIG. 8
[0045] (e.g., with a chamfer angle of 20 degrees, or another suitable chamfer angle) to
assist with mating the add-in card 500 to the baseboard.
[0046] Aspects of the present disclosure may provide one or more advantages over current
power delivery systems for add-in cards. For instance, an edge connector solution
according to the present disclosure has the potential advantage of lower cost and/or
preserving cooling airflow, as well as largely maintaining backward-compatibility
with existing PCIe hardware. In addition, aspects may provide for full backward compatibility
with previous revisions of PCI Express specifications (e.g., generations 1.0 through
4.0) by providing power delivery through existing, but otherwise unused features of
PCIe card geometry. Unlike the existing power/signal pins in the PCIe CEM connector
(e.g., through edge finger tab region 504), the new connectors may be configured specifically
for power delivery. As a result, the current carrying capacity of such connectors
would likely far exceed the demand of the card. Further, aspects of the present disclosure
may meet the immediate need for higher power cards for compute-intensive applications,
obviating the need for cabled solutions, which would add cost, block airflow, and
introduce mechanical obstructions in the chassis. Some aspects may also make use of
relatively unused areas of both the system baseboard and the add-in card, preserving
printed circuit board (PCB) routing avenues for both signal and power. Moreover, in
some embodiments, the additional power supply traces may be routed near the outer
edge of the baseboard, away from the high speed signaling traces used by the existing
edge connector. Additionally, the additional edge finger tabs may be tasked with power
delivery for a small number of networks (not signal integrity for a large number of
signals), which may permit the edge finger tabs to be designed with wide electrical
contacts that are relatively insensitive to misalignment. This may make it easier
to design the connector for robustness, when mated with a legacy add-in card, for
example.
[0047] Currently, the PCIe card electromechanical (CEM) specification allows for modest
power delivery from a baseboard through the existing edge finger tab region 504, by
means of +12 VDC and +3.3 VDC power rails. The maximum combined power provided by
the +12V and +3.3Vcard edge connector pins is 75 Watts (75W), which is delivered through
five +12V pins, three +3.3V pins, and a number of ground pins. While the quantity
of pins assigned to ground numbers between to 9 and 68 (depending on the card length,
x1, x16, etc.), only three ground pins are adjacent to the +12V pins, and those also
serve as ground returns for three nearby +3.3V supply pins. Further, since a single
metal connector pin geometry is used for power, high speed data, and ground functions,
the pins and mating add-in card edge finger tabs are not optimized for power delivery.
Recent improvements to the connector contact design have focused entirely on high
speed data performance, with no attempt to improve power delivery. As a result, the
existing PCIe card edge connector is ill-suited for high power delivery. Delivery
of additional power from the baseboard would require an additional power connector.
[0048] In backplane applications, system components are on orthogonal PCB panels, similar
to the PCIe baseboard and add-in card. In these applications it is common to employ
connectors optimized for high speed signaling and separate connectors that are designed
for dense power delivery (high current). This multi-connector approach can potentially
increase cost, but may save PCB real estate, and maximize performance for both. Backplane
connectors typically have two mating components that are mounted separately to the
baseboard and backplane, and joined during system assembly. These connectors are generally
more costly, and may be adapted for use in high-end systems.
[0049] Card-edge connectors serve the same role, connecting a baseboard to an orthogonal
PCB panel, but, in contrast, they are provided as single components that are mounted
only to the baseboard, accepting mating edge finger contacts manufactured from the
mating PCB card edge. In general, the manufacture of card edge connectors is straightforward,
with identical connector contacts inserted into a single molded plastic housing component.
Some card edge connectors, unlike the PCIe connector, are specifically designed for
power delivery. Many of these would be suitable candidates for supplying the needed
high current/high voltage delivery. Further, some hybrid card edge connectors even
provide separately optimized signal and power delivery contacts in different sections
of the same connector body.
[0050] An additional PCIe PCB edge finger tab to accommodate edge fingers to engage a power
connector would be simple to implement. A corresponding extension to the existing
baseboard edge connector to form a new hybrid power/ground PCIe connector would also
be straightforward. However, there are shortcomings to this edge connector approach.
For instance, there is no suitable solution for implementing a new PCB edge finger
tab to deliver the needed power PCIe through a new or modified baseboard connector
without violating the PCIe CEM specification. The add-in card outline is strictly
defined by the specification, so the addition of the incremental edge finger tabs
extending beyond the established card perimeter would violate backward compatibility.
The downward protrusion of the edge additional finger tab would cause mechanical interference
with baseboard-mounted components on some legacy system baseboards.
[0051] FIG. 6 illustrates an embodiment of coupling between an example add-in card 601 and
an example edge connector 611. The add-in card 601 includes an edge finger tab region
602 with electrical contacts 603. The edge finger tab region 602 includes two separate
edge finger tabs 602A, 602B. As shown, the edge finger tab region 602 is configured
to be mated with the connection mechanism 614, such that the contacts 603 (or "edge
fingers") and contacts 615 are in electrical connection with one another when the
card 601 is mated with the edge connector 611. The electrical contacts 603 may provide
signaling and/or power delivery to components of the add-in card 601 when coupled
to the electrical contacts 615. The add-in card 601 also includes an additional edge
finger tab 604 with an electrical contact 605. In some embodiments, the contact 605
may be located at the bottom 3.45 mm of the tab 604, which may be approximately 10
mm wide. Currently, PCIe specifications mandate that this area is to be free of components,
surface metal, and solder mask; however, in accordance with the present disclosure,
this area may be reassigned as a new edge finger region for a power connector. As
shown, the edge finger tab 604 is configured to be mated with the connection mechanism
616, such that the contact 605 and contacts 617 are in electrical connection with
one another when the card 601 is mated with the edge connector 611. In the example
shown, the edge finger tab region 602 corresponds to a PCIe x1 add-in card. The edge
finger tab region 602 may thus be referred to as a PCIe-compatible edge finger region,
and the connection mechanism 614 may be referred to as a PCIe-compatible connection
mechanism.
[0052] The connection mechanism 614 includes electrical contacts 615 that are configured
to couple the electrical contacts 603 of the edge finger tab region 602 to traces
or components of a baseboard (e.g., to an interconnect architecture such as a PCIe-compatible
interconnect architecture as discussed below with respect to FIG. 10). Likewise, the
connection mechanism 616 includes electrical contacts 617 that are configured to couple
the electrical contact 605 of the edge finger tab 604 to traces or components of a
baseboard (e.g., to a power delivery architecture as discussed below with respect
to FIG. 10). As shown in FIG. 6, the additional connection mechanism 616 may be at
a different height than the PCIe-compatible connection mechanism 614, to account for
a height difference between the additional edge finger tab 604 and the PCIe-compatible
edge finger tab region 602 of the card 601. In the example shown, the edge connector
611 houses both the electrical contacts 615 and 617. However, in some embodiments,
the electrical contacts 615 and 617 may be housed in separate edge connectors.
[0053] In the example shown, the edge finger tab 604 is formed in the same manner as a "blocking
tab" described in PCIe specification, which prevents the card 601 from being inserted
into legacy PCI edge connectors. The edge finger tab 604 may be considered to be generally
rectangular shaped. The electrical contact 605 may provide power delivery (in additional
to the power delivery provided through one or more of electrical contacts 603) to
components of the add-in card 601. In some embodiments, the edge finger tab 604 may
include additional contacts to provide signaling to/from the add-in card 601.
[0054] The location of the tab 604 may be advantageous since all PCIe-compatible add-in
cards are require to have the legacy PCI blocking tab in the same position. In addition,
since the location of the tab 604 lies near the rear panel of a chassis in which the
card 601 would be placed, the system baseboard may easily implement a 48 VDC power
plane/rail in this area. Moreover, this area of the system baseboard is not crucial
for high speed signal routing, and the crucial high-speed PCIe bus between a CPU (or
other root complex device) and the PCIe connector of the system baseboard would typically
not transit the shadow of the blocking tab, so additional baseboard routing layers
could more easily be re-tasked as high-power routing without affecting existing PCB
routing. Further, since this area is proximate to the rear panel of the chassis, it
may facilitate connection to an external 48V power source, with very inconsequential
conductive power loss.
[0055] Advantages of migrating to 48 VDC rail usage in system chassis need not be confined
to providing additional power to high-power (e.g., >300 W) PCIe add-in cards. For
example, many system components (including chassis and component fans, disk drives
& other storage media, and any lower power devices) may be able to reduce copper loss
and its associated chassis heat production with a 48 VDC power rail. In addition,
using an external power source may reduce system heating by relocating power conversion
(e.g., from 120 VAC to 12VDC) from inside the chassis to the external 48 VDC source.
Because of these considerations, lower power add-in cards, and add-in cards in x1,
x4, and x8 lengths could all easily tap into a 48 V bus, and shifting low power add-in
cards (e.g., x1 cards) to 48 VDC may also incrementally benefit system cooling. Therefore,
in some instances, placing an additional edge finger tab in the location shown in
FIG. 6 may be a preferred solution.
[0056] The location of the tab 604 may also provide backward compatibility with baseboards
that are designed according to older PCIe specifications. For instance, a 48V-compatible
add-in card placed into a legacy PCIe Generation 1, 2, 3, or 4 chassis would have
its edge finger tab 604 extending from the card over the system baseboard. However,
the tab would not be energized, since they would be designed to accept power from
the system board connector. In addition, a legacy PCIe Generation 1, 2, 3, or 4 add-in
card would have no exposed conductive edge finger on the blocking tab, and only the
electrically non-conductive bare FR4 fiberglass board material would engage a 48 V
power connector on the system baseboard. In embodiments where the blocking tab has
no chamfer on its leading edge, greater insertion force for the add-in card may be
needed, but the connector would be designed to accept this tab without suffering damage.
[0057] FIG. 7 illustrates another embodiment of coupling between an example add-in card
701 and an example edge connector 711. The add-in card 701 includes an edge finger
tab 702 with electrical contacts 703 ("edge fingers"). As shown, the edge finger tab
702 is configured to be mated with the connection mechanism 714, such that the contacts
703 and contacts 715 are in electrical connection with one another when the card 701
is mated with the edge connector 711. The electrical contacts 703 may provide signaling
and/or power delivery to components of the add-in card 701 when coupled to the electrical
contacts 715. The add-in card 701 also includes an additional edge finger tab 704
with an electrical contact 705. In some embodiments, the contact 705 may be located
on the bottom 5 mm of the hockey stick shaped tab 704, which may be approximately
12.7 mm wide (though, in some cases, the area useable for an edge finger electrical
contact may be narrower, e.g., approximately 10 mm). Currently, PCIe specifications
mandate that this area is to be free of components, surface metal, and solder mask;
however, in accordance with the present disclosure, this area may be reassigned as
a new edge finger region for a power connector. As shown, the edge finger tab 704
is configured to be mated with the connection mechanism 716, such that the contact
705 and contacts 717 are in electrical connection with one another when the card 701
is mated with the edge connector 711.
[0058] In the example shown, the edge finger tab 702 is part of a PCIe x16 add-in card 701.
The edge finger tab 702 may thus be referred to as a PCIe-compatible edge finger tab,
and the connection mechanism 714 may be referred to as a PCIe-compatible connection
mechanism. The connection mechanism 714 includes electrical contacts 715 that are
configured to couple the electrical contacts 703 of the edge finger tab 702 to traces
or components of a baseboard (e.g., to an interconnect architecture such as a PCIe-compatible
interconnect architecture as discussed below with respect to FIG. 10). Likewise, the
connection mechanism 716 includes electrical contacts 717 that are configured to couple
the electrical contact 705 of the edge finger tab 704 to traces or components of a
baseboard (e.g., to a power delivery architecture as discussed below with respect
to FIG. 10). As shown in FIG. 7, the additional connection mechanism 716 may be at
a different height than the PCIe-compatible connection mechanism 714, to account for
a height difference between the additional edge finger tab 704 and the PCIe-compatible
edge finger tab 702 of the card 701. In the example shown, the edge connector 711
houses both the electrical contacts 715 and 717. However, in some embodiments, the
electrical contacts 715 and 717 may be housed in separate edge connectors.
[0059] In the example shown, the edge finger tab 704 is formed in the same manner as a "hockey
stick feature" described in PCIe specifications, which is typically configured to
engage a retention mechanism of a baseboard. The edge finger tab 704 may be considered
to be generally hockey stick shaped. The electrical contact 705 may provide power
delivery (in additional to the power delivery provided through one or more of electrical
contacts 703) to components of the add-in card 701. In some embodiments, the edge
finger tab 704 may include additional contacts to provide signaling to/from the add-in
card 701.
[0060] The location of the tab 704 may have similar advantages to those described above
with respect to the blocking tab location (e.g., the location of the tab 604 in FIG.
6). Since the vast majority of high-power add-in card devices (e.g., >300W) implement
a x16 card edge interface, the "hockey stick" location (e.g., the location of tab
704 in FIG. 7) would be proximate to the end of the PCIe edge finger region. The location
of the tab 704 may also provide backward compatibility as well. For instance, a legacy
system board (PCIe Generation 1.0, 2.0, or 3.0, for example) mounting a x16 connector
would necessarily have a keep-out in the area of the hockey stick shaped tab 704.
The tab 704 and its exposed metal edge fingers would, in most cases, not engage a
mating baseboard retention mechanism, since they are already very uncommon, and any
retention mechanism, if present, would likely be made of a non-conductive material
(e.g., an extension of the plastic PCIe connector body). In the unlikely event that
a system baseboard has a metal hockey stick retention mechanism, the exposed terminals
would not be energized, and would be shorted at worst. In addition, if a legacy add-in
card (PCIe Generation 1.0, 2.0, or 3.0, for example) mounting a x16 connector has
a hockey stick retention feature (which is uncommon), it would not have exposed metal
edge fingers. As with the corresponding blocking tab solution (e.g., that shown in
FIG. 6), the hockey stick would engage the baseboard power connector with only bare
PCB material, such as FR4, introducing no electrical risk to either component. Here
too, the connector would be designed robustly, with the ability to accept the square-edged,
non-chamfered leading edge of the hockey stick.
[0061] While the discussions above with respect to FIGS. 5-7 suggest that the power source
is a 48 VDC power originating from outside of the chassis, a new power delivery path
could be any voltage, or combination of voltages, including supplemental 12 VDC power.
In addition, the 48VDC power source, or supplemental 12 VDC power source, may originate
from within the chassis (e.g., from a power supply mounted in the chassis).
[0062] FIG. 8 illustrates an embodiment of an example add-in card edge finger tab 801 with
a chamfered outer edge 810. The chamfered edge 810 may have a chamfer angle of 20
degrees in some embodiments, or may have another suitable chamfer angle. The chamfered
edge 810 may be implemented on any of the edge finger tabs of an add-in card described
above. For example, any one of the edge finger tabs 504, 506, or 508 of the add-in
card 500 of FIG. 5 may implement a chamfered edge similar to chamfered edge 810. The
edge finger tab 801 includes electrical contacts 802A, 802B on either side (which
may be referred to as "edge fingers"), which may be implemented similar to the electrical
contacts on the edge finger tabs described above.
[0063] FIGS. 9A-9D illustrate embodiments of edge card connectors 900 for communicably coupling
add-in cards to a baseboard and for providing additional power delivery to the add-in
card through additional connection mechanisms. In particular, FIGS. 9A-9D illustrate
top views of the example edge card connectors 900. Each of the example edge card connectors
900 includes a connection mechanism (e.g., 913, 922, 932, 941) with electrical contacts
that provide signaling and power delivery according to a PCIe-based specification
or protocol. Thus, the connection mechanisms 913, 922, 932, 941 may be considered
PCIe-compatible. For example, the connection mechanisms 913, 922, 932, 941 may mate
to a PCIe-compatible edge finger tab region of a PCIe-compatible add-in card (e.g.,
add-in card 500 of FIG. 5). The connection mechanisms 913, 922, 932, 941 may be an
x1, x4, x8, or x16 PCIe connection mechanism. In each of the examples shown, the additional
connection mechanisms are in-line with the PCIe-compatible connection mechanisms.
[0064] Each edge card connector 900 also includes at least one additional connection mechanism
(e.g., 911, 915, 921, 923, 931, 942) with electrical contacts that provide additional
power delivery to an add-in card (e.g., PCIe add-in card 500 of FIG. 5) that has corresponding
edge finger tabs configured to receive power from such mechanisms (e.g., edge finger
tabs 506, 508 of FIG. 5). In some embodiments, the additional connection mechanisms
may include electrical contacts that provide some signaling functionality as well
(e.g., signals to a power supply that indicate the presence or removal of a card from
the mechanism, to enable the power connection mechanism, etc.).
[0065] In FIG. 9A, the PCIe-compatible connection mechanism 913 is housed in an edge card
connector 912 that is separate from the edge card connectors 910, 914 that house the
additional connection mechanisms 911, 914, respectively, that are configured for additional
power delivery and signaling. By contrast, in FIG. 9B, the PCIe-compatible connection
mechanism 922 is housed in the same edge card connector 920 as the additional connection
mechanisms 921, 923, that are configured for additional power delivery and signaling.
Likewise, in FIGS. 9C, 9D, the PCIe-compatible connection mechanisms (932, 941) are
housed in the same edge card connector (930, 940) as the additional connection mechanisms
(931, 942) that are configured for additional power delivery and signaling.
[0066] In some embodiments, heights of the additional connection mechanisms (i.e., into
or out of the page with reference to FIGS. 9A-9D) may be different than the PCIe-compatible
connection mechanisms to account for a height difference between the additional edge
finger tabs of an add-in card and the PCIe-compatible edge finger of the card. For
example, as shown in FIG. 5, the edge finger tabs 504A, 504B extend further away from
the circuit board portion 502 than either of edge finger tabs 506, 508. To accommodate
for such a difference, the additional edge card connection mechanisms may be higher
than the PCIe-compatible edge card connection mechanisms as shown in FIGS. 6-7.
[0067] FIG. 10 illustrates an embodiment of a system 1000 that may incorporate PCIe-compatible
add-in cards with additional edge connectors for providing power delivery. One or
more aspects of the system 1000 may be incorporated into a computing system, such
as a personal computing system (e.g., a laptop, desktop, mobile, smartphone, Internet
of Things (IoT) device, smart appliance, gaming console, media console, etc.), a server
computing system (e.g., a rack server, blade server, tower server, rack scale server
architecture or other disaggregated server architecture), or another type of computing
system. In some cases, the components shown in FIG. 10 may be housed within a chassis.
The system 1000 shown in FIG. 10 is a simplified diagram of an example embodiment,
and the system 1000 may include fewer or additional components or features than those
shown in FIG. 10.
[0068] In the example shown, the system 1000 includes a baseboard 1002 that includes a controller
hub 1004, sockets 1006 to connect respective processor devices (e.g., CPUs, GPUs,
or other types of processor devices) to the baseboard 1002, and multiple connection
mechanisms 1010, 1012, 1014, 1016 for connecting respective peripheral devices (e.g.,
add-in cards) to the baseboard 1002. The controller hub 1004 communicably couples
the sockets 1006 to the connection mechanisms 1010, 1012A, 1014A, 1016A using links
1005, 1008. Collectively, the controller hub 1004 and the links 1005, 1008 may be
referred to as an interconnect architecture. In some embodiments, the controller hub
1004 may implement an interconnect protocol, such as a PCIe-based protocol, to facilitate
communications between processors housed by the sockets and peripheral devices housed
by the connection mechanisms.
[0069] The baseboard 1002 also includes a connector 1020 that includes one or more electrical
contacts to couple a power supply 1022 to the baseboard 1002. The baseboard 1002 further
includes power delivery traces 1018 that deliver power from the power supply 1022
to the additional connection mechanisms 1012B, 1014B, 1016B, 1016C. The baseboard
1002 may also include additional power delivery traces (not shown) that deliver power
to other components of the baseboard 1002, such as to the controller hub 1004, the
sockets 1006, and other connection mechanisms (e.g., 1010, 1012A, 1014A, 1016A). Collectively,
the power delivery lines 1018 (and those not shown in the simplified diagram of FIG.
10), connector 1020, and power supply 1022 may be referred to as a power delivery
architecture. In some embodiments, the power supply 1022 may deliver one or more of
a 3.3 VDC rail voltage, a 12 VDC rail voltage, a 48 VDC rail voltage, or another DC
rail voltage to the additional connection mechanisms 1012B, 1014B, 1016B, 1016C through
the power delivery architecture. In other embodiments, the power supply 1022 is supplemental
to another system power supply that provides a 12 VDC rail voltage and a 3.3 VDC rail
voltage to the connection mechanisms 1010, 1012A, 1014A, 1016A through the power delivery
architecture, and the power supply 1022 provides one of a 48 VDC rail voltage or a
supplemental 12 VDC rail voltage to the additional connection mechanisms 1012B, 1014B,
1016B, 1016C through the power delivery architecture.
[0070] In some embodiments, the power supply 1022 may be mounted external to a chassis in
which the baseboard 1002 resides. For instance, the chassis may include an internal
power supply to supply 3.3 VDC and 12 VDC rails to components of the baseboard 1002,
and the external power supply 1022 may be used to supply additional VDC rail voltages
to the additional power supply mechanisms 1012B, 1014B, 1016B, 1016C. In other embodiments,
the power supply 1022 is located inside a chassis in which the baseboard 1002 resides.
In some embodiments, the additional power delivery traces 1018 may be routed away
from the high speed signaling traces 1008 (e.g., near the outer edge of the baseboard
1002, such as near a rear end of a system chassis in which the baseboard is located)
connected to the existing connection mechanisms 1010, 1012A, 1014A, 1016A, as shown
in FIG. 10. In some embodiments, the connector 1020 may be located closer to an outer
edge of the baseboard (e.g., on the left side of the baseboard 1002 in FIG. 10) such
that the connector 1020 is closer to the connection mechanisms 1014B, 1016B, which
may reduce the length of the power delivery traces 1018 on the baseboard 1002 and
minimize any potential interference with the signaling traces 1008.
[0071] Each of the example connection mechanisms 1010, 1012A, 1014A, 1016A include electrical
contacts that provide signaling and power delivery according to a PCIe-based specification
or protocol. Thus, the connection mechanisms 1010, 1012A, 1014A, 1016A may be considered
PCIe-compatible. For example, the connection mechanisms 1010, 1012A, 1014A, 1016A
may be an x1, x4, x8, or x16 PCIe edge connector. The connection mechanisms 1012B,
1014B, 1016A, 1016B include electrical contacts that may provide additional power
delivery to a peripheral device (e.g., PCIe add-in card 500 of FIG. 5) that has corresponding
edge finger tabs configured to receive power from such mechanisms (e.g., edge finger
tabs 506, 508 of FIG. 5). In the example shown, the PCIe-compatible connection mechanisms
(e.g., 1010, 1012A, 1014A, 1016A) are housed in separate edge card connectors from
the connection mechanisms configured for additional power delivery (e.g., 1012B, 1014B,
1016A, 1016B). However, in some embodiments, the two types of connection mechanisms
may be housed in the same edge card connector (e.g., as shown in FIGS. 6-7).
[0072] Further, the example system 1000 includes an additional power connector 1023 that
may be used to connect to an additional edge finger of an add-in card (e.g., edge
finger tabs 506, 508 of FIG. 5) that is in one of the slots of the system 1000 that
does not include an additional connection mechanism. For example, an add-in card with
an additional edge finger to provide additional power delivery (e.g., edge finger
tab 604 of FIG. 6 or edge finger tab 704 of FIG. 7) may be inserted into the slot
associated with connection mechanism 1010. A cable may be connected to the additional
edge finger and then connected to the power connector 1023 or directly to the power
supply 1022 to provide the additional power delivery to the add-in card through its
additional edge finger, even though the slot does not include an additional connection
mechanism (like the other slots of system 1000).
[0073] Note that the apparatuses, methods, and systems described above may be implemented
in any electronic device or system as aforementioned. As specific illustrations, the
figures described below provide exemplary systems for utilizing the present disclosure.
As the systems below are described in more detail, a number of different interconnects
are disclosed, described, and revisited from the discussion above. And as is readily
apparent, the advances described above may be applied to any of those interconnects,
fabrics, or architectures. For instance, a host and device may be implemented, which
are equipped with functionality to implement the features discussed in the examples
above, in any one of a variety of computing architectures (e.g., using any one of
a variety of different interconnects or fabrics).
[0074] Referring to FIG. 11, an embodiment of a block diagram for a computing system including
a multicore processor is depicted. Processor 1100 includes any processor or processing
device, such as a microprocessor, an embedded processor, a digital signal processor
(DSP), a network processor, a handheld processor, an application processor, a co-processor,
a system on a chip (SOC), or other device to execute code. Processor 1100, in one
embodiment, includes at least two cores-core 1101 and 1102, which may include asymmetric
cores or symmetric cores (the illustrated embodiment). However, processor 1100 may
include any number of processing elements that may be symmetric or asymmetric.
[0075] In one embodiment, a processing element refers to hardware or logic to support a
software thread. Examples of hardware processing elements include: a thread unit,
a thread slot, a thread, a process unit, a context, a context unit, a logical processor,
a hardware thread, a core, and/or any other element, which is capable of holding a
state for a processor, such as an execution state or architectural state. In other
words, a processing element, in one embodiment, refers to any hardware capable of
being independently associated with code, such as a software thread, operating system,
application, or other code. A physical processor (or processor socket) typically refers
to an integrated circuit, which potentially includes any number of other processing
elements, such as cores or hardware threads.
[0076] A core often refers to logic located on an integrated circuit capable of maintaining
an independent architectural state, wherein each independently maintained architectural
state is associated with at least some dedicated execution resources. In contrast
to cores, a hardware thread typically refers to any logic located on an integrated
circuit capable of maintaining an independent architectural state, wherein the independently
maintained architectural states share access to execution resources. As can be seen,
when certain resources are shared and others are dedicated to an architectural state,
the line between the nomenclature of a hardware thread and core overlaps. Yet often,
a core and a hardware thread are viewed by an operating system as individual logical
processors, where the operating system is able to individually schedule operations
on each logical processor.
[0077] Physical processor 1100, as illustrated in FIG. 11, includes two cores-core 1101
and 1102. Here, core 1101 and 1102 are considered symmetric cores, i.e. cores with
the same configurations, functional units, and/or logic. In another embodiment, core
1101 includes an out-of-order processor core, while core 1102 includes an in-order
processor core. However, cores 1101 and 1102 may be individually selected from any
type of core, such as a native core, a software managed core, a core adapted to execute
a native Instruction Set Architecture (ISA), a core adapted to execute a translated
Instruction Set Architecture (ISA), a co-designed core, or other known core. In a
heterogeneous core environment (i.e. asymmetric cores), some form of translation,
such a binary translation, may be utilized to schedule or execute code on one or both
cores. Yet to further the discussion, the functional units illustrated in core 1101
are described in further detail below, as the units in core 1102 operate in a similar
manner in the depicted embodiment.
[0078] As depicted, core 1101 includes two hardware threads 1101a and 1101b, which may also
be referred to as hardware thread slots 1101a and 1101b. Therefore, software entities,
such as an operating system, in one embodiment potentially view processor 1100 as
four separate processors, i.e., four logical processors or processing elements capable
of executing four software threads concurrently. As alluded to above, a first thread
is associated with architecture state registers 1101 a, a second thread is associated
with architecture state registers 1101b, a third thread may be associated with architecture
state registers 1102a, and a fourth thread may be associated with architecture state
registers 1102b. Here, each of the architecture state registers (1101a, 1101b, 1102a,
and 1102b) may be referred to as processing elements, thread slots, or thread units,
as described above. As illustrated, architecture state registers 1101a are replicated
in architecture state registers 1101b, so individual architecture states/contexts
are capable of being stored for logical processor 1101a and logical processor 1101b.
In core 1101, other smaller resources, such as instruction pointers and renaming logic
in allocator and renamer block 1130 may also be replicated for threads 1101a and 1101b.
Some resources, such as re-order buffers in reorder/retirement unit 1135, ILTB 1120,
load/store buffers, and queues may be shared through partitioning. Other resources,
such as general purpose internal registers, page-table base register(s), low-level
data-cache and data-TLB 1115, execution unit(s) 1140, and portions of out-of-order
unit 1135 are potentially fully shared.
[0079] Processor 1100 often includes other resources, which may be fully shared, shared
through partitioning, or dedicated by/to processing elements. In FIG. 11, an embodiment
of a purely exemplary processor with illustrative logical units/resources of a processor
is illustrated. Note that a processor may include, or omit, any of these functional
units, as well as include any other known functional units, logic, or firmware not
depicted. As illustrated, core 1101 includes a simplified, representative out-of-order
(OOO) processor core. But an in-order processor may be utilized in different embodiments.
The OOO core includes a branch target buffer 1120 to predict branches to be executed/taken
and an instruction-translation buffer (I-TLB) 1120 to store address translation entries
for instructions.
[0080] Core 1101 further includes decode module 1125 coupled to fetch unit 1120 to decode
fetched elements. Fetch logic, in one embodiment, includes individual sequencers associated
with thread slots 1101a, 1101b, respectively. Usually core 1101 is associated with
a first ISA, which defines/specifies instructions executable on processor 1100. Often
machine code instructions that are part of the first ISA include a portion of the
instruction (referred to as an opcode), which references/specifies an instruction
or operation to be performed. Decode logic 1125 includes circuitry that recognizes
these instructions from their opcodes and passes the decoded instructions on in the
pipeline for processing as defined by the first ISA. For example, as discussed in
more detail below decoders 1125, in one embodiment, include logic designed or adapted
to recognize specific instructions, such as transactional instruction. As a result
of the recognition by decoders 1125, the architecture or core 1101 takes specific,
predefined actions to perform tasks associated with the appropriate instruction. It
is important to note that any of the tasks, blocks, operations, and methods described
herein may be performed in response to a single or multiple instructions; some of
which may be new sor old instructions. Note decoders 1126, in one embodiment, recognize
the same ISA (or a subset thereof). Alternatively, in a heterogeneous core environment,
decoders 1126 recognize a second ISA (either a subset of the first ISA or a distinct
ISA).
[0081] In one example, allocator and renamer block 1130 includes an allocator to reserve
resources, such as register files to store instruction processing results. However,
threads 1101a and 1101b are potentially capable of out-of-order execution, where allocator
and renamer block 1130 also reserves other resources, such as reorder buffers to track
instruction results. Unit 1130 may also include a register renamer to rename program/instruction
reference registers to other registers internal to processor 1100. Reorder/retirement
unit 1135 includes components, such as the reorder buffers mentioned above, load buffers,
and store buffers, to support out-of-order execution and later in-order retirement
of instructions executed out-of-order.
[0082] Scheduler and execution unit(s) block 1140, in one embodiment, includes a scheduler
unit to schedule instructions/operation on execution units. For example, a floating
point instruction is scheduled on a port of an execution unit that has an available
floating point execution unit. Register files associated with the execution units
are also included to store information instruction processing results. Exemplary execution
units include a floating point execution unit, an integer execution unit, a jump execution
unit, a load execution unit, a store execution unit, and other known execution units.
[0083] Lower level data cache and data translation buffer (D-TLB) 1150 are coupled to execution
unit(s) 1140. The data cache is to store recently used/operated on elements, such
as data operands, which are potentially held in memory coherency states. The D-TLB
is to store recent virtual/linear to physical address translations. As a specific
example, a processor may include a page table structure to break physical memory into
a plurality of virtual pages.
[0084] Here, cores 1101 and 1102 share access to higher-level or further-out cache, such
as a second level cache associated with on-chip interface 1110. Note that higher-level
or further-out refers to cache levels increasing or getting further way from the execution
unit(s). In one embodiment, higher-level cache is a last-level data cache-last cache
in the memory hierarchy on processor 1100-such as a second or third level data cache.
However, higher level cache is not so limited, as it may be associated with or include
an instruction cache. A trace cache-a type of instruction cache-instead may be coupled
after decoder 1125 to store recently decoded traces. Here, an instruction potentially
refers to a macro-instruction (i.e. a general instruction recognized by the decoders),
which may decode into a number of micro-instructions (micro-operations).
[0085] In the depicted configuration, processor 1100 also includes on-chip interface module
1110. Historically, a memory controller, which is described in more detail below,
has been included in a computing system external to processor 1100. In this scenario,
on-chip interface 1110 is to communicate with devices external to processor 1100,
such as system memory 1175, a chipset (often including a memory controller hub to
connect to memory 1175 and an I/O controller hub to connect peripheral devices), a
memory controller hub, a northbridge, or other integrated circuit. And in this scenario,
bus 1105 may include any known interconnect, such as multi-drop bus, a point-to-point
interconnect, a serial interconnect, a parallel bus, a coherent (e.g. cache coherent)
bus, a layered protocol architecture, a differential bus, and a GTL bus.
[0086] Memory 1175 may be dedicated to processor 1100 or shared with other devices in a
system. Common examples of types of memory 1175 include DRAM, SRAM, non-volatile memory
(NV memory), and other known storage devices. Note that device 1180 may include a
graphic accelerator, processor or card coupled to a memory controller hub, data storage
coupled to an I/O controller hub, a wireless transceiver, a flash device, an audio
controller, a network controller, or other known device.
[0087] Recently however, as more logic and devices are being integrated on a single die,
such as SOC, each of these devices may be incorporated on processor 1100. For example
in one embodiment, a memory controller hub is on the same package and/or die with
processor 1100. Here, a portion of the core (an on-core portion) 1110 includes one
or more controller(s) for interfacing with other devices such as memory 1175 or a
graphics device 1180. The configuration including an interconnect and controllers
for interfacing with such devices is often referred to as an on-core (or un-core configuration).
As an example, on-chip interface 1110 includes a ring interconnect for on-chip communication
and a high-speed serial point-to-point link 1105 for off-chip communication. Yet,
in the SOC environment, even more devices, such as the network interface, co-processors,
memory 1175, graphics processor 1180, and any other known computer devices/interface
may be integrated on a single die or integrated circuit to provide small form factor
with high functionality and low power consumption.
[0088] In one embodiment, processor 1100 is capable of executing a compiler, optimization,
and/or translator code 1177 to compile, translate, and/or optimize application code
1176 to support the apparatus and methods described herein or to interface therewith.
A compiler often includes a program or set of programs to translate source text/code
into target text/code. Usually, compilation of program/application code with a compiler
is done in multiple phases and passes to transform hi-level programming language code
into low-level machine or assembly language code. Yet, single pass compilers may still
be utilized for simple compilation. A compiler may utilize any known compilation techniques
and perform any known compiler operations, such as lexical analysis, preprocessing,
parsing, semantic analysis, code generation, code transformation, and code optimization.
[0089] Larger compilers often include multiple phases, but most often these phases are included
within two general phases: (1) a front-end, i.e. generally where syntactic processing,
semantic processing, and some transformation/optimization may take place, and (2)
a back-end, i.e. generally where analysis, transformations, optimizations, and code
generation takes place. Some compilers refer to a middle, which illustrates the blurring
of delineation between a front-end and back end of a compiler. As a result, reference
to insertion, association, generation, or other operation of a compiler may take place
in any of the aforementioned phases or passes, as well as any other known phases or
passes of a compiler. As an illustrative example, a compiler potentially inserts operations,
calls, functions, etc. in one or more phases of compilation, such as insertion of
calls/operations in a front-end phase of compilation and then transformation of the
calls/operations into lower-level code during a transformation phase. Note that during
dynamic compilation, compiler code or dynamic optimization code may insert such operations/calls,
as well as optimize the code for execution during runtime. As a specific illustrative
example, binary code (already compiled code) may be dynamically optimized during runtime.
Here, the program code may include the dynamic optimization code, the binary code,
or a combination thereof.
[0090] Similar to a compiler, a translator, such as a binary translator, translates code
either statically or dynamically to optimize and/or translate code. Therefore, reference
to execution of code, application code, program code, or other software environment
may refer to: (1) execution of a compiler program(s), optimization code optimizer,
or translator either dynamically or statically, to compile program code, to maintain
software structures, to perform other operations, to optimize code, or to translate
code; (2) execution of main program code including operations/calls, such as application
code that has been optimized/compiled; (3) execution of other program code, such as
libraries, associated with the main program code to maintain software structures,
to perform other software related operations, or to optimize code; or (4) a combination
thereof.
[0091] Referring now to FIG. 12, shown is a block diagram of another system 1200 in accordance
with an embodiment of the present disclosure. As shown in FIG. 12, multiprocessor
system 1200 is a point-to-point interconnect system, and includes a first processor
1270 and a second processor 1280 coupled via a point-to-point interconnect 1250. Each
of processors 1270 and 1280 may be some version of a processor. In one embodiment,
1252 and 1254 are part of a serial, point-to-point coherent interconnect fabric, such
as a high-performance architecture. As a result, certain embodiments may be implemented
within the QPI architecture.
[0092] While shown with only two processors 1270, 1280, it is to be understood that the
scope of the present disclosure is not so limited. In other embodiments, one or more
additional processors may be present in a given processor.
[0093] Processors 1270 and 1280 are shown including integrated memory controller units 1272
and 1282, respectively. Processor 1270 also includes as part of its bus controller
units point-to-point (P-P) interfaces 1276 and 1278; similarly, second processor 1280
includes P-P interfaces 1286 and 1288. Processors 1270, 1280 may exchange information
via a point-to-point (P-P) interface 1250 using P-P interface circuits 1278, 1288.
As shown in FIG. 12, IMCs 1272 and 1282 couple the processors to respective memories,
namely a memory 1232 and a memory 1234, which may be portions of main memory locally
attached to the respective processors.
[0094] Processors 1270, 1280 each exchange information with a chipset 1290 via individual
P-P interfaces 1252, 1254 using point to point interface circuits 1276, 1294, 1286,
1298. Chipset 1290 also exchanges information with a high-performance graphics circuit
1238 via an interface circuit 1292 along a high-performance graphics interconnect
1239.
[0095] A shared cache (not shown) may be included in either processor or outside of both
processors; yet connected with the processors via P-P interconnect, such that either
or both processors' local cache information may be stored in the shared cache if a
processor is placed into a low power mode.
[0096] Chipset 1290 may be coupled to a first bus 1216 via an interface 1296. In one embodiment,
first bus 1216 may be a Peripheral Component Interconnect (PCI) bus, or a bus such
as a PCI Express bus or another third generation I/O interconnect bus, although the
scope of the present disclosure is not so limited.
[0097] As shown in FIG. 12, various I/O devices 1214 are coupled to first bus 1216, along
with a bus bridge 1218 which couples first bus 1216 to a second bus 1220. In one embodiment,
second bus 1220 includes a low pin count (LPC) bus. Various devices are coupled to
second bus 1220 including, for example, a keyboard and/or mouse 1222, communication
devices 1227 and a storage unit 1228 such as a disk drive or other mass storage device
which often includes instructions/code and data 1230, in one embodiment. Further,
an audio I/O 1224 is shown coupled to second bus 1220. Note that other architectures
are possible, where the included components and interconnect architectures vary. For
example, instead of the point-to-point architecture of FIG. 12, a system may implement
a multi-drop bus or other such architecture.
[0098] The foregoing disclosure has presented a number of example mechanisms for delivering
power to PCIe add-in cards through additional edge finger tabs. It should be appreciated
that other mechanisms may be provided in addition to those identified above without
departing from the more generalized principles contained within this disclosure. For
instance, while some of the example power delivery mechanisms discussed herein were
described with reference to PCIe or PCIe-based protocols, it should be appreciated
that similar, corresponding enhancements may be made to other interconnect protocols,
such OpenCAPI™, Gen-Z™, UPI, Universal Serial Bus, (USB), Cache Coherent Interconnect
for Accelerators (CCIX™), Advanced Micro Device™'s (AMD™) Infinity™, Common Communication
Interface (CCI), or Qualcomm™'s Centriq™ interconnect, among others.
[0099] While the present disclosure has been described with respect to a limited number
of embodiments, those skilled in the art will appreciate numerous modifications and
variations therefrom. It is intended that the appended claims cover all such modifications
and variations as fall within the true spirit and scope of this present disclosure.
[0100] A design may go through various stages, from creation to simulation to fabrication.
Data representing a design may represent the design in a number of manners. First,
as is useful in simulations, the hardware may be represented using a hardware description
language or another functional description language. Additionally, a circuit level
model with logic and/or transistor gates may be produced at some stages of the design
process. Furthermore, most designs, at some stage, reach a level of data representing
the physical placement of various devices in the hardware model. In the case where
conventional semiconductor fabrication techniques are used, the data representing
the hardware model may be the data specifying the presence or absence of various features
on different mask layers for masks used to produce the integrated circuit. In any
representation of the design, the data may be stored in any form of a machine readable
medium. A memory or a magnetic or optical storage such as a disc may be the machine
readable medium to store information transmitted via optical or electrical wave modulated
or otherwise generated to transmit such information. When an electrical carrier wave
indicating or carrying the code or design is transmitted, to the extent that copying,
buffering, or re-transmission of the electrical signal is performed, a new copy is
made. Thus, a communication provider or a network provider may store on a tangible,
machine-readable medium, at least temporarily, an article, such as information encoded
into a carrier wave, embodying techniques of embodiments of the present disclosure.
[0101] A module as used herein refers to any combination of hardware, software, and/or firmware.
As an example, a module includes hardware, such as a micro-controller, associated
with a non-transitory medium to store code adapted to be executed by the micro-controller.
Therefore, reference to a module, in one embodiment, refers to the hardware, which
is specifically configured to recognize and/or execute the code to be held on a non-transitory
medium. Furthermore, in another embodiment, use of a module refers to the non-transitory
medium including the code, which is specifically adapted to be executed by the microcontroller
to perform predetermined operations. And as can be inferred, in yet another embodiment,
the term module (in this example) may refer to the combination of the microcontroller
and the non-transitory medium. Often module boundaries that are illustrated as separate
commonly vary and potentially overlap. For example, a first and a second module may
share hardware, software, firmware, or a combination thereof, while potentially retaining
some independent hardware, software, or firmware. In one embodiment, use of the term
logic includes hardware, such as transistors, registers, or other hardware, such as
programmable logic devices.
[0102] Use of the phrase 'configured to,' in one embodiment, refers to arranging, putting
together, manufacturing, offering to sell, importing and/or designing an apparatus,
hardware, logic, or element to perform a designated or determined task. In this example,
an apparatus or element thereof that is not operating is still 'configured to' perform
a designated task if it is designed, coupled, and/or interconnected to perform said
designated task. As a purely illustrative example, a logic gate may provide a 0 or
a 1 during operation. But a logic gate 'configured to' provide an enable signal to
a clock does not include every potential logic gate that may provide a 1 or 0. Instead,
the logic gate is one coupled in some manner that during operation the 1 or 0 output
is to enable the clock. Note once again that use of the term 'configured to' does
not require operation, but instead focus on the latent state of an apparatus, hardware,
and/or element, where in the latent state the apparatus, hardware, and/or element
is designed to perform a particular task when the apparatus, hardware, and/or element
is operating.
[0103] Furthermore, use of the phrases 'to,' 'capable of/to,' and or 'operable to,' in one
embodiment, refers to some apparatus, logic, hardware, and/or element designed in
such a way to enable use of the apparatus, logic, hardware, and/or element in a specified
manner. Note as above that use of to, capable to, or operable to, in one embodiment,
refers to the latent state of an apparatus, logic, hardware, and/or element, where
the apparatus, logic, hardware, and/or element is not operating but is designed in
such a manner to enable use of an apparatus in a specified manner.
[0104] A value, as used herein, includes any known representation of a number, a state,
a logical state, or a binary logical state. Often, the use of logic levels, logic
values, or logical values is also referred to as 1's and 0's, which simply represents
binary logic states. For example, a 1 refers to a high logic level and 0 refers to
a low logic level. In one embodiment, a storage cell, such as a transistor or flash
cell, may be capable of holding a single logical value or multiple logical values.
However, other representations of values in computer systems have been used. For example
the decimal number ten may also be represented as a binary value of 1010 and a hexadecimal
letter A. Therefore, a value includes any representation of information capable of
being held in a computer system.
[0105] Moreover, states may be represented by values or portions of values. As an example,
a first value, such as a logical one, may represent a default or initial state, while
a second value, such as a logical zero, may represent a non-default state. In addition,
the terms reset and set, in one embodiment, refer to a default and an updated value
or state, respectively. For example, a default value potentially includes a high logical
value, i.e. reset, while an updated value potentially includes a low logical value,
i.e. set. Note that any combination of values may be utilized to represent any number
of states.
[0106] The embodiments of methods, hardware, software, firmware or code set forth above
may be implemented via instructions or code stored on a machine-accessible, machine
readable, computer accessible, or computer readable medium which are executable by
a processing element. A non-transitory machine-accessible/readable medium includes
any mechanism that provides (i.e., stores and/or transmits) information in a form
readable by a machine, such as a computer or electronic system. For example, a non-transitory
machine-accessible medium includes random-access memory (RAM), such as static RAM
(SRAM) or dynamic RAM (DRAM); ROM; magnetic or optical storage medium; flash memory
devices; electrical storage devices; optical storage devices; acoustical storage devices;
other form of storage devices for holding information received from transitory (propagated)
signals (e.g., carrier waves, infrared signals, digital signals); etc., which are
to be distinguished from the non-transitory mediums that may receive information there
from.
[0107] Instructions used to program logic to perform certain embodiments may be stored within
a memory in the system, such as DRAM, cache, flash memory, or other storage. Furthermore,
the instructions can be distributed via a network or by way of other computer readable
media. Thus a machine-readable medium may include any mechanism for storing or transmitting
information in a form readable by a machine (e.g., a computer), but is not limited
to, floppy diskettes, optical disks, Compact Disc, Read-Only Memory (CD-ROMs), and
magnetooptical disks, Read-Only Memory (ROMs), Random Access Memory (RAM), Erasable
Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only
Memory (EEPROM), magnetic or optical cards, flash memory, or a tangible, machine-readable
storage used in the transmission of information over the Internet via electrical,
optical, acoustical or other forms of propagated signals (e.g., carrier waves, infrared
signals, digital signals, etc.). Accordingly, the computer-readable medium includes
any type of tangible machine-readable medium suitable for storing or transmitting
electronic instructions or information in a form readable by a machine (e.g., a computer).
[0108] The following examples pertain to embodiments in accordance with this Specification.
Example 1 includes a device that includes: a circuit board comprising a plurality
of circuit components; a first edge finger tab extending from the circuit board, wherein
the first edge finger tab comprises a plurality of electrical contacts to provide
signaling to and from particular circuit components of the circuit board, and the
first edge finger tab is to mate with a Peripheral Component Interconnect Express
(PCIe)-compatible edge card connection mechanism of a baseboard; and a second edge
finger tab extending from the circuit board, wherein the second edge finger tab comprises
one or more electrical contacts to provide power delivery to the circuit board, and
the second edge finger tab is to mate with a second edge card connection mechanism
of the baseboard.
Example 2 includes the subject matter of Example 1, and optionally, wherein the second
edge finger tab is between the first edge finger tab and an end of the device that
is to face an outer edge of the baseboard when the device is mated with the baseboard.
Example 3 includes the subject matter of Examples 1 or 2, and optionally, wherein
the second edge finger tab is to prevent the device from being inserted into a legacy
PCI edge card connection mechanism.
Example 4 includes the subject matter of Example 1, and optionally, wherein the second
edge finger tab is between the first edge finger tab and an end of the device that
is to face inward relative to a baseboard when the device is mated with the baseboard.
Example 5 includes the subject matter of Examples 1 or 4, and optionally, wherein
the second edge finger tab is to engage with a retention mechanism of a baseboard
when the device is mated with the baseboard.
Example 6 includes the subject matter of any one of Examples 1-5, and optionally,
wherein the second edge finger tab comprises one or more electrical contacts to provide
signaling to or from one or more of the circuit components of the circuit board portion.
Example 7 includes the subject matter of any one of Examples 1-6, and optionally,
wherein an outer end of the second edge finger tab is chamfered.
Example 8 includes the subject matter of any one of Examples 1-7, and optionally,
further comprising a third edge finger tab extending from the circuit board, wherein
the third edge finger tab comprises one or more electrical contacts to provide power
delivery to the circuit board and is adapted to mate with a third baseboard connection
mechanism.
Example 9 includes the subject matter of any one of Examples 1-8, and optionally,
wherein the electrical contacts of the second edge finger tab are to alternatively
provide one of a 12 VDC rail voltage or a 48 VDC rail voltage to circuit components
of the circuit board.
Example 10 includes a baseboard that includes: one or more electrical contacts to
receive power from a power supply; one or more sockets to each house a processor;
an interconnect architecture for connecting the one or more sockets to at least one
peripheral devices according to a Peripheral Component Interconnect Express (PCIe)-based
interconnect protocol; a first edge card connection mechanism comprising electrical
contacts to couple a particular peripheral device to the interconnect architecture
when a PCIe-compatible edge finger tab region of the particular peripheral device
is mated with the first edge card connection mechanism; and a second edge card connection
mechanism in-line with the first edge card mechanism, the second edge card connection
mechanism comprising electrical contacts to provide power delivery from the power
supply to the particular peripheral device when a second edge finger tab of the particular
peripheral device is mated with the second edge card connection mechanism.
Example 11 includes the subject matter of Example 10, and optionally, wherein the
second edge card connection mechanism is between the first edge card connection mechanism
and an outer edge of the baseboard.
Example 12 includes the subject matter of Example 10, and optionally, wherein the
first edge card connection mechanism is between the second edge card connection mechanism
and an outer edge of the baseboard.
Example 13 includes the subject matter of Examples 10, 11, or 12, and optionally,
wherein the first and second edge card connection mechanisms are housed in the same
edge card connector on the baseboard.
Example 14 includes the subject matter of Examples 10, 11, or 12, and optionally,
wherein the first edge card connection mechanism is housed in a first edge card connector
of the baseboard, and the second edge card connection mechanism is housed in a second
edge card connector of the baseboard.
Example 15 includes the subject matter of any one of Examples 10-14, and optionally,
wherein the second edge card connection mechanism comprises electrical contacts to
provide signaling to or from the particular peripheral device in addition to power
delivery.
Example 16 includes the subject matter of any one of Examples 10-15, and optionally,
further comprising a third edge card connection in-line with the first and second
edge card connection mechanisms, the third edge card connection mechanism comprising
electrical contacts to provide power delivery from the power supply to the particular
peripheral device when a third edge finger tab of the particular peripheral device
is mated with the third edge card connection mechanism.
Example 17 includes a system that includes: a processor; an add-in card device; a
power supply; an interconnect architecture for connecting the processor to the add-in
card device according to a Peripheral Component Interconnect Express (PCIe)-based
interconnect protocol; and a power delivery architecture for delivering power from
the power supply to components of the system; wherein the add-in card device comprises:
a PCIe-compatible edge finger tab region comprising edge finger tabs coupling circuit
components of the add-in card device to the interconnect architecture through a first
edge card connection mechanism; and a second edge finger tab in-line with the tabs
of the PCIe-compatible edge finger tab region, the second edge finger tab coupling
circuit components of the add-in card device to the power delivery architecture through
a second edge card connection mechanism.
Example 18 includes the subject matter of Example 17, and optionally, wherein the
add-in card device further comprises a third edge finger tab in-line with the tabs
of the PCIe-compatible edge finger tab region, the third edge finger tab to couple
circuit components of the add-in card device to the power delivery architecture through
a third edge card connection mechanism.
Example 19 includes the subject matter of Example 17, and optionally, wherein the
first edge card connection mechanism is housed in a first edge card connector of a
baseboard, and the second edge card connection mechanism includes a cable coupling
the additional edge finger tab to the power supply.
Example 20 includes the subject matter of any one of Examples 17-19, and optionally,
wherein the power supply alternatively provides one of a 12 VDC rail voltage or a
48 VDC rail voltage, and the power delivery architecture is to deliver the rail voltage
provided by the power supply to the additional edge finger tab of the add-in card.
Example 21 includes the subject matter of any one of Examples 17-20, and optionally,
wherein the power supply is external to a chassis in which the add-in card is located.
Example 22 includes the subject matter of any one of Examples 17-21, and optionally,
wherein the power supply is a first power supply, the system further includes a second
power supply that provides a 12 VDC rail voltage and a 3.3 VDC rail voltage, and the
power delivery architecture delivers power from the second power supply to the add-in
card through the first edge card connection mechanism.
Example 23 includes the subject matter of any one of Examples 1-9, and optionally,
wherein the device is incorporated into a server architecture, such as a blade server
or rack mounted server.
Example 24 includes the subject matter of any one of Examples 10-16, and optionally,
wherein the baseboard is incorporated into a server architecture, such as a blade
server or rack mounted server.
Example 25 includes the subject matter of Example 17, and optionally, wherein the
add-in card device is configured according to any one of the Examples 1-9.
Example 26 includes the subject matter of Example 17, and optionally, wherein the
system further includes a baseboard configured according to any one of the Examples
10-16, wherein the add-in card is coupled to the baseboard.
Example 27 includes the subject matter of any one of Examples 1-8, and optionally,
wherein the second edge finger tab includes a PCIe-compatible feature that is typically
to prevent the device from being inserted into a legacy PCI edge card connection mechanism.
Example 28 includes the subject matter of any one of Examples 1-8, and optionally,
wherein the second edge finger tab includes a PCIe-compatible feature that is typically
to engage a retention mechanism of a baseboard.
Example 29 includes the subject matter of Example 17, and optionally, wherein the
second edge finger tab is compatible with a PCIe-compatible feature that is typically
to prevent the device from being inserted into a legacy PCI edge card connection mechanism.
Example 30 includes the subject matter of Example 17, and optionally, wherein the
second edge finger tab is compatible with a PCIe-compatible feature that is typically
to engage a retention mechanism of a baseboard.
Example 31 includes the subject matter of Examples 1, 2, or 3, and optionally, wherein
the second edge finger tab is generally rectangular shaped.
Example 32 includes the subject matter of Examples 1, 4, or 5, and optionally, wherein
the second edge finger tab is generally hockey stick shaped.
Example 33 includes the subject matter of Example 8, and optionally, further comprising
a first current blocking element coupled to the second edge finger tab and a second
current blocking element coupled to the third edge finger tab; wherein the first and
second current blocking elements are to selectively accept power from either the second
edge finger tab or the third edge finger tab.
Example 34 includes the subject matter of Example 18, and optionally, wherein the
add-in card further comprises a first current blocking element coupled to the additional
edge finger tab and a second current blocking element coupled to the third edge finger
tab; wherein the first and second current blocking elements are to selectively accept
power from either the additional edge finger tab or the third edge finger tab.
[0109] Reference throughout this specification to "one embodiment" or "an embodiment" means
that a particular feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the present disclosure. Thus,
the appearances of the phrases "in one embodiment" or "in an embodiment" in various
places throughout this specification are not necessarily all referring to the same
embodiment. Furthermore, the particular features, structures, or characteristics may
be combined in any suitable manner in one or more embodiments.
[0110] In the foregoing specification, a detailed description has been given with reference
to specific exemplary embodiments. It will, however, be evident that various modifications
and changes may be made thereto without departing from the broader spirit and scope
of the disclosure as set forth in the appended claims. The specification and drawings
are, accordingly, to be regarded in an illustrative sense rather than a restrictive
sense. Furthermore, the foregoing use of embodiment and other exemplarily language
does not necessarily refer to the same embodiment or the same example, but may refer
to different and distinct embodiments, as well as potentially the same embodiment.